Patent application number | Description | Published |
20080314021 | METHOD TO RE-OPEN ASH FILLED CHANNELS IN DIESEL PARTICULATE FILTERS - A method for determining a time duration and an amount of fuel to include within exhaust gases to facilitate sintering of ash within a diesel particulate filter to reopen ash filled channels in said diesel particulate filter. | 12-25-2008 |
20090158707 | ENGINE AFTER-TREATMENT CONTROLS USING DOSING BELOW CATALYST LIGHT-OFF TEMPERATURE - A method of controlling dosing of a hydrocarbon fuel into the exhaust gas of a combustion engine upstream of a particulate filter when the exhaust gas temperature into an oxidation catalyst upstream of a particulate filter has dropped below the light-off temperature of the catalyst. | 06-25-2009 |
20090199537 | METHODS TO PROTECT SELECTIVE CATALYST REDUCER AFTERTREATMENT DEVICES DURING UNCONTROLLED DIESEL PARTICULATE FILTER REGENERATION - The present invention is directed to a method to operate an electronically controlled internal combustion engine with an exhaust system equipped with a diesel particulate filter upstream of a selective catalyst reducer to protect the selective catalyst reducer from premature aging and failure caused by exhaust temperature heat generated during uncontrolled regeneration of the diesel particulate filter. | 08-13-2009 |
20090217645 | METHOD OF OPERATING AN INTERNAL COMBUSTION ENGINE TO HEAT UP A SELECTIVE CATALYST REDUCER - In one embodiment, the present invention relates to a method to operate an internal combustion engine equipped with an Electronic Control Unit (ECU) with memory, an exhaust system including a Diesel Oxidation Catalyst (DOC), a Diesel Particulate Filter (DPF), upstream of a Selective Catalyst Reducer (SCR). A doser is in the DPF and actuated by commands from the ECU. The method includes sensors at the DPF and SCR electronically connected to the ECU to transmit data signals indicative of operating conditions at the DPF and SCR. The method includes sensing the temperature at an outlet of the DPF and an inlet at the SCR determining whether that temperature is at least a predetermined temperature for a predetermined period of time, and introducing heat to the SCR to raise its temperature to a predetermined level for a predetermined period of time, such as light off temperature, to operate more efficiently. Heat may be introduced in the exhaust stream by engine thermal management strategies as well. | 09-03-2009 |
20090277158 | METHOD OF CONTROLLING HYDROCARBON ACCUMULATION IN A PARTICULATE FILTER UNDER CERTAIN OPERATING CONDITIONS - One embodiment of the invention includes a method of operating an internal combustion engine system comprising an engine, an oxidation catalyst, and a particulate filter, the method comprising: determining if the outlet temperature of exhaust gas from the oxidation catalyst is below a first temperature, measuring the time that the outlet temperature of exhaust gas from the oxidation catalyst is below the first temperature, determining if the measured time has exceeded a first time period, and if so, elevating the temperature of the exhaust gas exiting the oxidation catalyst. | 11-12-2009 |
20100206060 | ON-BOARD AFTERTREATMENT DEVICE TAIL PIPE HYDROCARBON SLIP CALCULATION - A method to determine hydrocarbon slip in a compression ignition engine equipped with an electronic control unit having memory and coupled to an exhaust gas aftertreatment system having a diesel oxidation catalyst, a diesel particulate filter, a selective catalyst reducer and a clean up diesel oxidation catalyst | 08-19-2010 |
20110239627 | APPARATUS AND METHOD FOR MONITORING OXIDATION CATALYST FUNCTIONALITY - Method and apparatus for evaluating an ammonia conversion efficiency of an ammonia oxidation (AMOX) catalyst for reducing ammonia and hydrocarbons present in an exhaust gas stream. The AMOX associated with an exhaust gas after-treatment system has a selective catalytic reduction (SCR) catalyst for reducing nitrogen oxides (NO | 10-06-2011 |
20120210700 | METHOD TO MONITOR PRESSURE DROP ACROSS A SELECTIVE CATALYST REDUCER FOR ENGINE AND EXHAUST AIRFLOW DIAGNOSTICS - A method to diagnose exhaust system malfunction in an electronically controlled internal combustion engine having an exhaust system and including a Selective Catalyst Reducer (SCR) is disclosed. The method may comprise determining ambient barometric pressure; determining a baseline curve of exhaust flow; and monitoring said exhaust flow rate for changes in exhaust flow rate compared to change of exhaust pressure across the SCR to diagnose exhaust system malfunction. | 08-23-2012 |